This is Steven Salzberg's blog on genomics, pseudoscience, medical breakthroughs, higher education, and other topics, including skepticism about unscientific medical practices. Here's where I can say what I really think about abuses and distortions of science, wherever I see them.

Sniffle. It's allergy season again. Do those shots work?

Ah, spring is in the air. The flowers are blooming and the trees are bursting into leaf.

For many of us, this time of year means one thing: allergies. The price of going outside for any length of time is sneezing and itchy eyes that last for many hours, even after we return indoors. Rather than going out and enjoying the warm air and colorful vegetation, we close the doors and windows and stock up on antihistamines and eye drops. Studies show that 20–40% of people in the U.S. have allergies.

Your local pharmacy has shelf after shelf of allergy treatments, ranging from mildly effective (Zyrtec and its equivalents) to laughably ineffective (anything homeopathic). But even the best pills have side effects, and they only serve to suppress the symptoms. As one study put it:

"Patients struggle to alleviate their misery, frequently self-adjusting their treatment regimen of over-the-counter and prescription medications because of lack of efficacy, deterioration of efficacy, lack of 24-hour relief, and bothersome side effects."

Isn't there a way to tell your body to just stop it already? After all, pollen is not a pathogen. Our misery is caused by our own immune system's over-reaction: it ramps up in response to the foreign particles (pollen) in our eyes and airways and creates a histamine reaction, which is simply not necessary.

None of the over-the-counter pills prevent this reaction, but they can dampen it–hence the term "antihistamine." However, what if there were a way to tell your body to simply chill out and ignore the pollen?

Well, maybe. You can get allergy shots. This is a surprisingly simple procedure: your doctor takes a small, diluted amount of the allergen (pollen, cat dander, etc.) and injects it into your arm. Over the course of many months, your doctor will very gradually increase the amount being injected. You have to go for the shots every week, and continue them for several years.

The question is, do they work? The answer is a qualified yes.

NIH and the Agency for Healthcare Research and Quality (AHRQ) have put together a long explainer of the evidence for and against allergy shots, which you can find at PubMed Health. The NIH study looked at 74 clinical studies of allergy shots. To save you some time, I'll cut to the chase: the evidence is quite good that shots work. Or, as the AHRQ study put it,

This might seem like pseudoscience, but it's not: what's happening is that your immune system is being de-sensitized to the allergen. It doesn't work for everyone, but in many people, this gradual de-sensitization trains their immune system not to react so badly. It's not necessarily permanent, either: after stopping the shots, allergies might re-appear after a few years.

So if you're looking out your window at the beautiful spring weather with a box of tissues by your side, maybe you have a way out. Talk to your doctor or visit the AAAAI site to find an allergy specialist. Don't expect miracles or a quick fix, but allergy shots are the best we've got, for now.